ML13171A278
| ML13171A278 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 05/16/2013 |
| From: | Beltz T Plant Licensing Branch III |
| To: | Loeffler R Northern States Power Co |
| References | |
| TAC ME8186 | |
| Download: ML13171A278 (4) | |
Text
1 NRR-PMDAPEm Resource From:
Beltz, Terry Sent:
Thursday, May 16, 2013 8:06 AM To:
'Loeffler, Richard A.'
Cc:
'Rippy, L. Randal'; 'Eckholt, Gene F.'; Carlson, Robert; McLellan, Thomas; Cheruvenki, Ganesh
Subject:
Monticello Nuclear Generating Plant - Request for Additional Information re: Fifth 10-Year Inservice Inspection Program Plan Review (TAC No. ME8186)
Attachments:
Monticello - Request for Additional Information - Fifth 10-Year Inservice Inspection Program Plan Review (TAC No ME8186).docx
Dear Mr. Loeffler:
By letter dated February 28, 2012 (Agencywide Documents Access and Management System (ADAMS)
Accession No. ML12060A298), Northern States Power Company - Minnesota, doing business as Xcel Energy, Inc., submitted its fifth 10-year Inservice Inspection (ISI) Program Plan in accordance with Title 10 of the Code of Federal Regulations (10 CFR), Part 50.55a, for the Monticello Nuclear Generating Plant.
The U.S. Nuclear Regulatory Commission (NRC) staff in the Vessels & Internals Integrity Branch and the Piping and NDE Branch of the Office of Nuclear Reactor Regulation is currently reviewing your submittal. The NRC staff has determined that additional information is required to complete its review. Draft requests for additional information were provided in an e-mail dated April 9, 2013 (ADAMS Accession No. ML13099A275).
The NRC staff and its contractors participated in a conference call with Xcel Energy on May 9, 2013, to discuss the draft RAIs and provide further clarification, as needed. At the conclusion of the conference call, it was determined that draft RAI Question 1 was no longer required, and RAI Question 4 (a comment) was understood and could be removed. Draft RAI Questions 2 and 3 will be formally issued and are provided as an attachment to this e-mail.
Please provide a response to the attached RAIs by June 14, 2013.
Please let me know if you have any questions or concerns.
Sincerely, Terry A. Beltz, Senior Project Manager Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation (301) 415-3049 Terry.Beltz@nrc.gov
Hearing Identifier:
NRR_PMDA Email Number:
727 Mail Envelope Properties (87B1F1BDFE5A554CA9DC5EAA75EB6D0DDDA384E779)
Subject:
Monticello Nuclear Generating Plant - Request for Additional Information re: Fifth 10-Year Inservice Inspection Program Plan Review (TAC No. ME8186)
Sent Date:
5/16/2013 8:05:48 AM Received Date:
5/16/2013 8:05:00 AM From:
Beltz, Terry Created By:
Terry.Beltz@nrc.gov Recipients:
"'Rippy, L. Randal'" <Randal.Rippy@xenuclear.com>
Tracking Status: None
"'Eckholt, Gene F.'" <Eugene.Eckholt@xenuclear.com>
Tracking Status: None "Carlson, Robert" <Robert.Carlson@nrc.gov>
Tracking Status: None "McLellan, Thomas" <Thomas.McLellan@nrc.gov>
Tracking Status: None "Cheruvenki, Ganesh" <Ganesh.Cheruvenki@nrc.gov>
Tracking Status: None
"'Loeffler, Richard A.'" <Richard.Loeffler@xenuclear.com>
Tracking Status: None Post Office:
HQCLSTR01.nrc.gov Files Size Date & Time MESSAGE 1691 5/16/2013 8:05:00 AM Monticello - Request for Additional Information - Fifth 10-Year Inservice Inspection Program Plan Review (TAC No ME8186).docx 21133 Options Priority:
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Recipients Received:
REQUEST FOR ADDITIONAL INFORMATION FROM THE OFFICE OF NUCLEAR REACTOR REGULATION REGARDING REVIEW OF THE FIFTH 10-YEAR INSERVICE INSPECTION PROGRAM PLAN NORTHERN STATES POWER COMPANY - MINNESOTA MONTICELLO NUCLEAR GENERATING PLANT DOCKET NO. 50-263 TAC NO. ME8186 INTRODUCTION By letter to the U.S. Nuclear Regulatory Commission (NRC) dated February 28, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12060A298), Northern States Power Company - Minnesota, doing business as Xcel Energy, Inc. (the licensee), submitted its fifth 10-year Inservice Inspection (ISI) Program Plan in accordance with Title 10 of the Code of Federal Regulations (10 CFR), Part 50.55a, for the Monticello Nuclear Generating Plant (MNGP). The licensee requested that the NRC staff review its proposed fifth 10-year ISI Program Plan for MNGP to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code),Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, inspection requirements. The applicable ASME Code,Section XI code of record for the MNGP Fifth 10-Year ISI Program Plan is the 2007 Edition through the 2008 Addenda.
The licensees risk-informed ISI program plan will be submitted at a later date and reviewed by the NRC staff in a separate report.
The NRC staff and Pacific Northwest National Laboratory have reviewed the information submitted by the licensee and, based on this review, determined that the following information is required to complete the evaluation.
REQUEST FOR ADDITIONAL INFORMATION
- 1.
In Section 3.0 and Appendix D of the submittal, the licensee stated that examinations of Class 1, 2, 3 components, including welded attachments and supports, are based on the requirements as defined in ASME Code Section XI Sections IWB-, IWC-, IWD-, and IWF-2000. The Bottom Head Drain Nozzle listed under ASME Code Category B-D is exempt per ASME Code IWB-1220(c).
Please verify there are not any other components being examined that fall under the provisions of IWB-, IWC-, and IWD-1220, Components Exempt from Examination, and IWF-1230, Supports Exempt from Examination.
2
- 2.
Appendix D, Inspection Plan and Schedule Tables 2.1 Category B-A, Item B1.11, Reactor Vessel circumferential shell welds - ASME Code Table IWB-2500-1, Category B-A, Item B1.11, states that all welds should be inspected.
Request for Alternative, RR-001, requires that all welds be examined at a reduced percentage of 2 to 3 percent associated with the intersection with longitudinal welds.
The licensee has listed only one out of four circumferential shell welds that are to be inspected for the fifth ten-year inservice inspection program plan.
Please explain the basis for examining only one of the four circumferential-to-axial intersecting areas for all RPV shell welds at MNGP.
2.2 Category B-K, Item B10.10, Pressure Vessel Welded Attachments - According to ASME Code Table IWB-2500-1, it is not permissible to defer examinations to the end of the interval. The examination of a larger component, such as the reactor vessel support skirt, should be performed in segments throughout the entire interval. The table lists the inspection taking place during the last period which is not permitted by IWB-2500.
Please verify and explain the schedule for examination of the reactor vessel support skirt.
2.3 Category B-K, Items B10.20 and B10.30, and Category C-C, Items C3.20 and C3.30, Piping and Pump Welded Attachment Welds - Notes 2 and 3, respectively, state that for piping and pump welded attachments, a sample of 10 percent of the welded attachments associated with the component supports selected for examination under IWF-2510 shall be examined. For Category B-K, there are a combined 50 piping and pump welded attachments and only three (3) are listed to be inspected. Additionally, for Category C-C, there are a combined 84 piping and pump welded attachments and only 3 are listed to be inspected. These do not total to 10 percent of the welded attachments.
Please explain why 10 percent of the piping and pump welded attachments for each category is not being met.
2.4 There appears to be inconsistencies in the Examination Percentage Required column shown in the inspection plan and schedule tables of Appendix D. For some categories (e.g., Category B-O), the licensee put the percentage of what would actually be inspected (12.5 percent) in lieu of what is actually required by ASME Code (10 percent).
For other categories (e.g., Category B-P), the licensee stated the percentage required by ASME Code (100 percent).
Please explain the differences between Appendix D, the Inspection Plan and Schedule Tables, and, specifically, items in the Examination Percentage Required column with those required by IWB-, IWC-, IWD-, and IWF-2000 in the ASME Code.